Laser powder bed fusion of Ti6Al4V using low-cost high efficiency 450 nm diode point melting


Aydin A., Cetin E., Erman S. C., Mumtaz K.

Journal of Materials Research and Technology, cilt.34, ss.2814-2827, 2025 (SCI-Expanded) identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 34
  • Basım Tarihi: 2025
  • Doi Numarası: 10.1016/j.jmrt.2024.12.252
  • Dergi Adı: Journal of Materials Research and Technology
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Compendex, INSPEC, Directory of Open Access Journals
  • Sayfa Sayıları: ss.2814-2827
  • Anahtar Kelimeler: Additive manufacturing, Diode point melting (DPM), Laser powder bed fusion, Microstructure, Process optimization, Ti6Al4V
  • Çukurova Üniversitesi Adresli: Hayır

Özet

Laser Powder Bed Fusion (LPBF) is a commonly used Additive Manufacturing (AM) method for the production of geometrically complex metal components that are used in high-value sectors. It uses high power fibre lasers directed by a galvanometric scanner to rapidly melt powdered feedstock. LPBF systems are expensive, making them inaccessible to many sectors and have challenges related to in-process thermal control, production of large components and scalability limitations. As an alternative to traditional LPBF, this study introduces Diode Point Melting (DPM), combining multiple low-power, energy efficient blue (450 nm) diode lasers into a single focal point. DPM's laser source is fixed to a scanning gantry axis that traverses across the powder bed, creating a low-cost alternative to traditional LPBF (∼x10 lower laser hardware cost). DPM processes slower than LPBF, generating reduced thermal gradients with improved material laser energy absorption due to use of a shorter laser wavelength. DPM processing of Ti6Al4V was undertaken using 38W creating samples that were 99.41% dense. DPM's slower melt pool solidification rate enabled the formation of a stable α + β phase creating harder samples. The grain size of Ti6Al4V samples fabricated using DPM were significantly larger compared to those produced by LPBF (grain size area ∼ x30 larger). Young's modulus of the samples produced via DPM was found to be higher than LPBF manufactured Ti6Al4V, indicating increased stiffness. DPM is a promising low-cost alternative to LPBF, offering the opportunity to make net-shape metal AM more widely accessible in both academic and industrial sectors.